Volume rendering is a set of techniques used to display a two-dimensional (2D) projection of a three-dimensional (3D) discretely sampled data set. One of the techniques used for volume rendering is ray-marching, which blends a collection of samples taken from a data set at a fixed step along each screen pixel's view-ray. Ray-marching produces accurate renditions and promises to remain a viable technique for volume rendering for the foreseeable future.